There are many different techniques for attaching a closure to a container. One such technique involves providing the closure and the container with mating threads. Although threaded closures can be made tamperproof, containers employing such closures are susceptible to leakage as a result of the wearing of the threads.
Closures can also be ultrasonically welded or glued to a container. Although ultrasonic welding and gluing avoid the leakage problem associated with a threaded connection, such techniques cannot be used when the container and closure are made from such materials as polyethylene and polypropylene, which are popular materials for making plastic containers.
Spin fusion is another technique for attaching a closure to a container. In accordance with the spin fusion technique, the closure is rotated relative to the container, the friction and resulting heat generated by the relative rotation of the closure and container melting a portion of the closure and/or container which, upon solidification, fuses the closure and container together. One problem associated with such a spin fusion technique involves the production of fines (i.e., small pieces of container and/or closure material) as a result of the rubbing contact between the closure and container during the spin fusion operation. If these fines are not collected, they can contaminate the contents of the container.